So, I checked the exact latitude and longitude of the two KLAX runway 24 glideslopes in default MSFS, vs. Navigraph vs. official FAA data, and they all match almost exactly.

FAA ILS 24R (IOSS) G/S

LAT: N33-57-2.41

LON: W118-24-18.52

 

DEFAULT NAVBLUE

LAT: N33-57-2.40

LON: W118-24-18.51

 

NAVIGRAPH

LAT: N33-57-2.40

LON: W118-24-18.51

The slight variation after the decimal point in the “seconds” values would amount to a position difference of about +/- 3 inches

The ILS 24L (IHQD) values were equally close to one another from all three sources.

 

Hi Jim,

Did you watch Crimplene's video (previous page/post) ?

Do yo also see a G/S dip when landing KLAX 06L ?

 

Note: MSFS's KLAX newest updated scenery I assume.

Edited January 12, 20233 yr by vonmar

3 hours ago, vonmar said:

Hi Jim,

Did you watch Crimplene's video (previous page/post) ?

Do yo also see a G/S dip when landing KLAX 06L ?

 

Note: MSFS's KLAX newest updated scenery I assume.

I have occasionally seen a slight momentary “wobble” in the glideslope at various airports. I think this is more in the way that the default nav receivers are coded, than in the simulated ILS in the scenery. I have never tried landing on runway 06 L or R at KLAX.

I have only the default KLAX (no payware or freeware KLAX add-ons.) I have landed on all 4 west-facing runways at KLAX at various times, and have never had any ILS issues.

Edited January 12, 20233 yr by JRBarrett

1 hour ago, JRBarrett said:

I have occasionally seen a slight momentary “wobble” in the glideslope at various airports. I think this is more in the way that the default nav receivers are coded, than in the simulated ILS in the scenery. I have never tried landing on runway 06 L or R at KLAX.

I have only the default KLAX (no payware or freeware KLAX add-ons.) I have landed on all 4 west-facing runways at KLAX at various times, and have never had any ILS issues.

Hello Jim,

Just to mention Crimplene's video (previous page/post) was more than a slight momentary “wobble”  in the G/S. You might want to have a look.

Also, MSFS's default KLAX got a free Update. Did you get it?

My last (video) test was KLAX 06L. Did you watch it?

Edit : Also, testing the G/S with the autopilot off.

Edited January 12, 20233 yr by vonmar

25 minutes ago, vonmar said:

Hello Jim,

Just to mention Crimplene's video (previous page/post) was more than a slight momentary “wobble”  in the G/S. You might want to have a look.

Also, MSFS's default KLAX got a free Update. Did you get it?

My last (video) test was KLAX 06L. Did you watch it?

Edit : Also, testing the G/S with the autopilot off.

I am in SU11 beta, so I assume if default KLAX has been updated, I have it.

The ILS definitions are separate and apart from the base airport scenery. The ILS definitions for all default airports are contained in the AIRAC files. Asobo updates those (from NavBlue) on a regular basis - though not always on the exact day that a new AIRAC is released. Navigraph always updates their AIRAC nav data for MSFS on the very day a new cycle takes effect, but of course you must run their data manager app to actually install the updates in MSFS.

I will watch your video shortly.

6 minutes ago, JRBarrett said:

.I will watch your video shortly.

I watched the clip. You would have to leave the autopilot engaged at least all the way to MDA to know if any glideslope fluctuations are due to deviations in the simulated ILS in the sim vs. piloting technique when hand-flying. It probably also depends on the particular aircraft your are flying - whether it uses default nav receiver code or a custom nav receiver (that may be the case with add-ons like the PMDG or Fenix, but I don’t know for sure).

On 1/7/2023 at 8:10 AM, crimplene said:

Could you name some examples? I did a lot of ILS and RNAV approaches in the past few weeks and can't remember a single one that was wrong.

This happened to me over a year ago but I think the airport code was UHPP, it's a single-runway airport on the eastern side of Russia and the LOC was lined up with the taxiway and not the runway. I did some googling after pulling a Harrison Ford in a 787 and found that airport's runway is actually the taxiway I landed on, they just haven't updated Bing to reflect the "old" runway being closed and the taxiway converted to a runway.  Google Maps shows the new runway, Bing shows the old runway, but the ILS is apparently updated to the new runway!

That was part of a trip around the world, and while that was the only one that was completely off the runway, I did come across a few that seemed slightly offset but they were all out in the middle of nowhere but nothing in the realm of the OP's "90%" figure.  Haven't had any issues with stuff in North America and Europe though, and I utilized the FBW320 Autoland in Beijing and Shanghai while landing in a blizzard, both touched down right on the aim points.  I've also used Autoland for a few airports in the US and have yet to come across any that didn't plop down right where they should have.

Finally a rl pilot noticed the issue too, so maybe some people will start to see it if it's not just a humble simmer claiming that something is wrong.

 

3 hours ago, Jeeeno said:

Finally a rl pilot noticed the issue too, so maybe some people will start to see it if it's not just a humble simmer claiming that something is wrong.

 

Yes, this was the thread I was thinking of when I saw this video. He demonstrates what I was talking about very well. Honestly, I can't imagine how some people have not noticed it.

The location of the glideslope antenna on any MSFS default airport runway is set by the nav data AIRAC files. In the case of default MSFS, those files are supplied by NavBlue. There is the option to use Navigraph for nav data, which I have done since MSFS was released. I have a utility program which can read the NAXxxxx.BGL files containing localizer and glideslope data. I will compare the Lat/Lon of the EDDL 23L glideslope in default NavBlue data vs. Navigraph to see if there is any significant difference.

Unfortunately I have no access to information as to the actual location of the navaids for German airports to confirm whether the G/S placement is correct in either NavBlue or Navigraph. That information is readily available for US airports at https://enasr.faa.gov/eNASR/nasr/Current

The PAPI light placement on the other hand is contained in the airport scenery BGL, and its accuracy depends on the scenery designer placing the PAPI object precisely where it is located in the real world. When I modified the scenery for my home airport to include new taxiways that were built after MSFS was released, I found the default PAPI was placed about 150 feet beyond where it should be. Since a lot of the default airports were built using a mostly automated process, this may be a common problem.

On 2/26/2023 at 4:17 PM, JRBarrett said:

The location of the glideslope antenna on any MSFS default airport runway is set by the nav data AIRAC files. In the case of default MSFS, those files are supplied by NavBlue. There is the option to use Navigraph for nav data, which I have done since MSFS was released. I have a utility program which can read the NAXxxxx.BGL files containing localizer and glideslope data. I will compare the Lat/Lon of the EDDL 23L glideslope in default NavBlue data vs. Navigraph to see if there is any significant difference.

Unfortunately I have no access to information as to the actual location of the navaids for German airports to confirm whether the G/S placement is correct in either NavBlue or Navigraph. That information is readily available for US airports at https://enasr.faa.gov/eNASR/nasr/Current

The PAPI light placement on the other hand is contained in the airport scenery BGL, and its accuracy depends on the scenery designer placing the PAPI object precisely where it is located in the real world. When I modified the scenery for my home airport to include new taxiways that were built after MSFS was released, I found the default PAPI was placed about 150 feet beyond where it should be. Since a lot of the default airports were built using a mostly automated process, this may be a common problem.

The problem is that also many payware sceneries have wrong GS/PAPI ...